DIABETES INSIPIDUS – THE COMPLEXITY OF THE SYNDROME

Abstract

ABSTRACT It is suggested that in diabetes insipidus the possibility should be entertained of simultaneous disturbances in several of the systems concerned with water conservation. Criteria for the analysis of the syndrome are redefined. To illustrate the complexity of the syndrome, five cases are reported in the dog, among the first thus defined to be extensively investigated in any species both in life and at necropsy. In one, the syndrome was ascribed primarily to hypothalamo-neurohypophysial inadequacy associated with inflammatory atrophy of the secretory system, and in the second primarily to vasopressin resistance associated with renal medullary fibrosis. In three cases, the response to exogenous and endogenous vasopressin was inconsistent with a primary neurohypophysial or renal abnormality. In all, there was evidence of a hepatic dysfunction, recovery from which in one case was associated with a remission of the diabetic symptoms. Of a number of possible contributory factors, including vasopressin-resistance, primary polydipsia and excessive vasopressin inactivation, the last seemed probably the most important.